Method of attenuating sound transmitted through a building structure

ABSTRACT

A method is provided for attenuating sound transmitted through a building structure. The method includes marketing an insulation product for installation in a cavity in the building structure wherein the insulation product has a thickness T greater than the depth D of the cavity. The insulation product is then compressed between the first and second covering members or materials. The insulation product produces a sound damping force upon the covering material.

TECHNICAL FIELD AND INDUSTRIAL APPLICABILITY OF THE INVENTION

This invention relates to fibrous insulation products of a type suitable for insulating buildings. More specifically, this invention pertains to methods for attenuating sound transmitted through a building structure in a more efficient and effective manner.

BACKGROUND OF THE INVENTION

Fibrous insulation products for insulating building structures including floors, ceilings and walls and more particularly the cavities between wall studs, floor joists and ceiling joists are well known in the art. Insulation in exterior walls primarily functions as thermal insulation to isolate the interior space of a building from ambient temperature extremes. In contrast, interior walls are often insulated to provide sound damping and attenuation. Insulation products useful for these purposes are disclosed in, for example, U.S. Pat. Nos. 4,702,046, 5,983,586, 6,128,884, 6,191,057, 6,484,463 and 6,901,711.

Generally, the insulation products of the prior art are cut to fill the entire length and width of the cavities so that there are no gaps between the insulation and the framing members forming the cavity. Often the insulation products are oversized in the length and width directions. When such products are utilized in walls they are compressed between the wall studs of the top and bottom plates of the framework and forced into the cavity to provide a friction fit that holds the insulation product in place until the cavity is closed with a sheathing or finishing material such as drywall.

The present invention relates to an improved method for providing sound insulation in a building structure such as a floor, ceiling or wall. Instead of compressing the insulation product between the components of the structural framework, the insulation product is compressed between the opposing wall covering materials. As a result, the insulation product produces a sound damping force upon the covering materials. Surprisingly, it has been found that enhanced sound attenuation may be achieved in this manner even without filling the entire length and width of the cavity with the insulation material. Accordingly, the method allows one to provide enhanced acoustic performance from a given amount of insulation material thereby increasing efficiencies.

SUMMARY OF THE INVENTION

In accordance with the purposes of the present invention as described herein, a method is provided for attenuating sound transmitted through a building structure. That building structure includes a frame that supports a first covering material and a second covering material. A cavity is formed by the frame between the first covering material and the second covering material. The cavity has a depth D, a width W₁, and a length L₁. The method comprises the marketing of an insulation product for installation in the cavity wherein the insulation product has a thickness T greater than the depth D of the cavity. When installed the insulation product is compressed between the first and second covering materials. As a result of this compression, the insulation product produces a sound damping force upon the covering materials to more efficiently and effectively dampen sound from being transmitted through the building structure.

In accordance with additional aspects of the present method, the method further includes providing insulation product with one of: (a) a width W₂ less than the width W₁ of the cavity, (b) a length L₂ less than the length L₁ of the cavity and (c) a width W₂ less than the width W₁ and a length L₂ less than the length L₁ of the cavity. The method further includes providing the insulation product with a batt of insulation material and a facing. Further, the method includes providing adhesive on the facing to allow the insulation product to be temporarily held in the cavity until the cavity is closed by the first and second covering materials.

In accordance with an additional aspect of the present invention a method is provided for insulating a wall section made from framing members, a first covering material and a second covering material. The framing members define a wall cavity having a length L₁, a width W₁ and a depth D. The method comprises placing an insulation product in the wall cavity having a thickness T greater than the depth D. In addition, the method further includes saving material used to make the insulating product by providing the insulating product with (a) a length L₂ less than the length L₁, (b) a width W₂ less than the width W₁ or (c) a length L₂ less than the length L₁ and a width W₂ less than the width W₁. The method further includes the step of compressing the insulation product in the wall cavity between the first and second covering materials.

In one embodiment the method further includes temporarily securing the insulation product to one of the framing members before compressing the insulation product between the first and second covering materials. Where the framing members include a top plate, a bottom plate, a first stud and a second stud the method includes securing the insulation product to the top plate. This may be done by pinning, adhering and/or stapling the insulation product to the top plate. Alternatively, the method may include temporarily securing the insulation product to the first covering material before installing the second covering material and compressing the insulation product.

In the following description there is shown and described several different embodiments of the invention, simply by way of illustration of some of the modes best suited to carry out the invention. As it will be realized, the invention is capable of other different embodiments and its several details are capable of modification in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings incorporated herein and forming a part of the specification, illustrate several aspects of the present invention, and together with the description serve to explain certain principles of the invention. In the drawing:

FIG. 1 is a perspective view of an insulation product;

FIG. 2 is a schematic block diagram of the method of the present invention;

FIG. 3 a is an elevation showing the positioning of the insulation product in the wall cavity formed by the top plate, bottom plate and wall studs;

FIG. 3 b is a side elevational view demonstrating the positioning of the insulation product in the wall cavity; and

FIG. 3 c is a side elevational view demonstrating the compression of the insulation product between the finishing materials that close the cavity.

Reference is now made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawing.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

A method is provided for attenuating sound transmitted through a building structure such as a floor, ceiling or wall wherein the building structure includes a frame that supports a first covering material and a second covering material. A cavity is formed between the frame and the first covering material and the second covering material. The cavity has a depth D, a width W₁ and a length L₁. The method may be broadly described as comprising the marketing of an insulation product for installation in the cavity wherein the insulation product has a thickness T greater than the depth D of the cavity. When the insulation product is compressed between the first and second covering materials, the insulation product produces a sound damping pressure upon the covering materials. That pressure typically is in a range from about 2 to about 10 lbs/ft².

Significantly, it has been found that the entire length and width of the cavity need not be filled with the insulation material. As a result the present method allows one to achieve approved acoustic performance and sound attenuation for a given volume of insulating material. Thus the present method is more effective and efficient in providing sound attenuation than prior art approaches.

One insulation product that may be utilized in the present invention is illustrated in FIG. 1. This insulation product 10 includes an elongated batt 12 of fibrous insulation material having a first major face 14 (see also FIG. 3 b). A facing 16 covers the first major face 14. The facing 16 may be secured to the first major face 14 of the elongated batt 12 by any appropriate means known in the art including but not limited to an appropriate adhesive or binder layer.

The fibrous insulation material of the elongated batt 12 may be made from mineral fibers, organic fibers and mixtures thereof. The mineral fibers most typically comprise glass fibers although other mineral fibers such as rock, slag or basalt may be utilized.

The organic fibers typically include polymeric material from which fibers of suitable length, strength, durability and insulation characteristics can be formed. Suitable polymer materials for making the polymer fibers include, but are not limited to polyolefins and polyesters. More specifically, suitable polymer materials include but are not limited to polyethylene terephthalate, polypropylene, polyphenylene sulfide, nylon, polycarbonate, polystyrene and polyamide.

Typically the elongated batt 12 of fibrous insulation material has a density within a range of from about 0.3 to about 1.0 pounds per cubic foot (pcf) although densities outside this range may also be utilized. The fibers utilized in the insulation material may include straight fibers, irregular fibers and mixtures thereof. The elongated batt 12 may be a conformable body such as described in U.S. Pat. No. 6,128,884 and may be binderless. Alternatively, the elongated batt 12 may incorporate some binder material in fiber, film, or powder form. Typically, the elongated batt 12 of fibrous insulation material includes from about 3 to about 7 weight percent organic binder.

The facing 16 may be made from any appropriate material known in the art to be useful as a facing for an insulation product to be used in insulating a building. Such material includes but is not limited to metal foils, polymer films and even dual layer facings comprising a co-extruded polymer film with a barrier layer and a bonding layer of the type described in, for example, U.S. Pat. No. 6,191,057.

A method of insulating a wall section made from framing members, a first covering material and a second covering material will now be described in detail with reference to FIG. 2. The framing members define a wall cavity having a length L₁, a width W₁ and a depth D. As illustrated, the method includes the step 20 of placing an insulation product in the wall cavity having a thickness T greater than the depth D. Further, the method includes the step 22 of saving material used to make the insulation product by providing the insulation product with (a) a length L₂ less than the length L₁, (b) a width W₂ less than the width W₁, or (c) a length L₂ less than the length L₁ and a width W₂ less than the width W₁. In addition, the method includes the step 24 of compressing the insulation product in the wall cavity between the first and second covering materials.

When insulating a wall W, the framing members typically include a top plate T, a bottom plate B, a first stud S₁ and a second stud S₂ that define a square or rectangular cavity C (see FIG. 3 a). In this situation the method may further include the step 26 of securing the insulation product to the top plate T. This may be done, for example, by pinning, adhering or stapling an exposed margin 17 of the facing 16 to the top plate T as illustrated (note staples G).

In accordance with an alternative approach the method includes the step 28 of temporarily securing the insulation product in the cavity by temporarily securing the insulation product to the first covering material F₁, (FIG. 3 b) before installing the second covering material F₂ and compressing the insulation product to hold it in position (FIG. 3 c). This may be accomplished using fasteners or adhesive.

The improved acoustical performance provided by the present method for a given weight of insulation material is best illustrated with reference to the following comparison.

In a first trial a 3.5 inch thick insulation batt was positioned in a cavity in a wall structure having a depth of 3.5 inches in accordance with prior art teachings so as to completely fill the cavity in the length and width directions with a single layer of insulation material. In a second trial, the same insulation batt was folded in half or doubled over and placed in the same cavity. While the insulation batt only filled half of the width of the cavity in the second trial, the acoustic performance was improved (see following table) by an average of 10 decibels over the all important sound frequencies between 200 and 4000 Hertz.

Base Case-No Conventional Insulated Narrow Batt - cavity fill Wall Cavity - Centered in cavity Wood stud Wall cavity filled - Conventional batt Frequency wall assembly full width batts folded in half 80 21 19 18 100 16 15 15 125 13 13 10 160 12 17 18 200 16 25 27 250 24 34 35 315 28 36 38 400 32 39 42 500 32 41 44 630 36 43 47 800 40 47 50 1000 42 50 52 1250 44 51 54 1600 47 52 56 2000 45 52 55 2500 38 44 47 3150 36 41 42 4000 38 44 44 5000 44 47 51 Average dB difference from uninsulated Base Case wall (⅓ octave bands 200–4000 Hz): 10 The damping pressure exerted by the insulation batt on the wall covering materials in the second trial was about 8 lbs/ft².

The foregoing description of the preferred embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. The drawings and preferred embodiments do not and are not intended to limit the ordinary meaning of the claims in their fair and broad interpretation in any way. 

1. A method of attenuating sound transmitted through a building structure wherein said building structure includes a frame that supports a first covering material and a second covering material, a cavity being formed between said frame, said first covering material and said second covering material, said cavity having a depth D, a width W₁ and a length L₁, said method comprising: marketing an insulation product for installation in said cavity wherein said insulation product has a thickness T greater than the depth D of said cavity whereby when said insulation product is compressed between said first covering material and said second covering material, said insulation product produces a sound damping force upon said first covering material and said second covering material.
 2. The method of claim 1 further including providing said insulation product with a width W₂ less than said width W₁ of said cavity.
 3. The method of claim 1, further including providing said insulation product with a length L₂ less than said length L₁, of said cavity.
 4. The method of claim 1, further including providing said insulation product with one of; (a.) a width W₂ less than said width W₁ of said cavity; (b.) a length L₂ less than said length L₁, of said cavity; and (c.) a width W₂ less than said width W₁ of said cavity and a length L₂ less than said length L₁ of said cavity.
 5. The method of claim 4, including providing said insulation product with a batt of insulation material and a facing.
 6. The method of claim 5, including providing adhesive on said facing to allow said insulation product to be temporarily held in said cavity until said cavity is closed by said first covering material and said second covering material.
 7. A method of insulating a wall section made from framing members, a first covering material and a second covering material wherein said framing members define a wall cavity having a length L₁, width W₁ and a depth D, said method comprising: placing an insulation product in said wall cavity having a thickness T greater than said depth D; saving material used to make said insulation product by providing said insulation product with (a) a length L₂ less than said length L₁, (b) a width W₂ less than said width W₁ or (c) a length L₂ less than said length L₁ and a width W₂ less than said width W₁; and compressing said insulation product in said wall cavity between said first and second covering materials.
 8. The method of claim 7 further including temporarily securing said insulation product to one of said framing members before compressing said insulation product between said first and second covering.
 9. The method of claim 8, wherein said flaming members include a top plate a bottom plate, a first stud and a second stud and said method includes securing said product to said top plate.
 10. The method of claim 9, including pinning said insulation product to said top plate.
 11. The method of claim 9, including adhering said insulation product to said top plate.
 12. The method of claim 9, including stapling said insulation product to said top plate.
 13. The method of claim 7, further including temporarily securing said insulation product to said first covering material before installing said second covering material and compressing said insulation product.
 14. The method of claim 13, wherein said securing step includes adhering said insulation product to said first covering material.
 15. The method of claim 13, wherein said securing step includes fastening said insulation product to said first covering material with a fastener. 